The packaging of candy and other food products in bags presents some problems. First among these is that the equipment for doing so must be constructed in such a way that it is readily sanitizable and otherwise meets standards of cleanliness such as, in the United States, regulations of the Federal Government.
Powdery food products as well as other pulverulent materials present special problems. The "dumping" of such a product into a bag results in airborne dust particles which tend to adhere to bag surfaces and inhibit proper formation of a heat seal to close a loaded bag and complete a package. Similarly if liquids are being packaged and a surface to be sealed is wet or if, during the loading process, other substances become adhered to surfaces to be sealed, proper sealing is inhibited.
The use of chains of pre-opened bags to form packages is now well known. Such chains of bags are disclosed and claimed in U.S. Pat. No. 3,254,828 entitled FLEXIBLE CONTAINER STRIPS (The Autobag Patent). A commercial version of a machine described and claimed in U.S. Pat. No. 3,965,653 entitled PACKAGING APPARATUS, and in other patents deriving from the applications that resulted in this patent, (the H-100 Patents) has been sold commercially by Automated Packaging Systems, Inc. under the designation H-100. While the H-100 machine has been very successful it is a machine in which bag separation and sealing of a loaded bag are completed before a succeeding bag is positioned in an opened condition at a load station and loaded. This sequential operation is a limiting factor on the speed at which packaging operations are performed.
Another machine which has been successfully used commercially, for bagging chickens in operations where the bags are not sealed is sold by Automated Packaging as a part of its PHS-2000 system and is the commercial version of the machine described and claimed in U.S. Pat. No. 4,651,506 entitled PACKAGING APPARATUS AND METHOD (The Chicken Bagger Patent).
A limitation on the use of chains of interconnected pre-opened bags has been when heavy or bulky products are packaged it becomes difficult to properly register the face of the bag with the back of the bag to effect a high quality, neat appearing seal. While special techniques and equipment such as that described in U.S. Pat. No. 3,956,866 entitled PACKAGING METHOD AND APPARATUS have been developed to assist in the proper packaging of relatively bulky and/or heavy materials, the use of pre-opened bags on a roll has none the less been limited to moderate size bags. The essentially bulk packaging of such products as rock candy and granular dog food have at most been packaged with chains of pre-opened bags in very limited quantities if at all.
While attempts have been made to produce chains of interconnected pre-opened bags suitable for use in packaging pulverulent products such as that described and claimed in U.S. Pat. No. 3,948,015 entitled PACKAGING SYSTEM none have enjoyed success. One problem with the system described in this referenced patent was the bag opening was of limited size inhibiting high volume efficient production packaging of pulverulent materials.
In the packaging of some materials it is desirable to charge gas into the package or to evacuate the package or both. In the past little if any commercial packaging has been performed with pre-opened interconnected bags produced packages in which the contents are either gas charged or evacuated.